Question

HI;

In my iPhone App in UipickerView can I move picker Values up or down Programmatically

To add effect of an animation like picker is moving itself only
for that

[picker selectRow:0 inComponent:0 animated:YES]; 

----    ---
//here I need Some time delay

[picker selectRow:3 inComponent:0 animated:YES]; 

How can I give some time delay between execution of this two statements

Please help and Suggest

Thanks

Answer 1

If you want to add some delay, you could use :

[NSThread sleepForTimeInterval:0.5];

But this will block your application, so it can be better to use a timer :

//In your method :
[picker selectRow:0 inComponent:0 animated:YES]; 

[NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(animatePickerTimer:) userInfo:picker repeats:NO];


//In the same class


-(void)animatePickerTimer:(NSTimer *)timer;
{
    [self performSelectorOnMainThread:@selector(animatePicker:) withObject:(UIPickerView *)timer.userInfo waitUntilDone:NO];

    //Not sure if this is required, since the timer does not repeat
    [timer invalidate];
}

-(void)animatePicker:(UIPickerView *)picker
{
[picker selectRow:3 inComponent:0 animated:YES];
}

This should be performed on main thread, since UIKit is not thread safe